Description

https://docs.mongodb.com/manual/tutorial/restore-sharded-cluster/

Prior to this step on the shards, this step is missing:

Remove the

from the admin.system.version collection

That document contains the minimum timestamp and election term for inclusion in queries to the CSRS. If the original cluster's CSRS experienced elections, the election term will be > 1 in that document. For example:

{ "_id" : "minOpTimeRecovery", "configsvrConnectionString" : "configRepl/localhost:39008,localhost:39009,localhost:39010", "minOpTime" : { "ts" : Timestamp(1547112229, 5), "t" : NumberLong(2) }, "minOpTimeUpdaters" : 0, "shardName" : "shard01" }

Election term is value of t here:

"t" : NumberLong(2) 

Meanwhile, the newly restored CSRS will start out with election term = 1. If the document is not removed and the term > 1 in that document, it will result in unsatisfiable queries to the CSRS (since the CSRS term will never match the query term). This leaves the restored cluster in a degraded state.

Scope of changes

Impact to Other Docs

MVP (Work and Date)

Resources (Scope or Design Docs, Invision, etc.)